Gasteria (2020)

Text and Photos by Nikki Murdick (August 2020)

This brief article is an introduction to a fascinating group of plants from South Africa – the gasterias. During the show and tell Zoom club meeting in August, I will be showing some of my collection of these plants.

The name Gasteria comes from the Greek word “gaster,” which means stomach and refers to the bulbous shape of some of the flowers. Gasterias are a group of popular, undemanding and easy to grow succulent plants that are endemic to South Africa. Most grow no more than 30 to 60 miles from the coast. There are two species that are found outside South Africa – one just over the border in Namibia and the other just over the border in Swaziland.

History

The first written record of these plants was in the 1680s, when Hendrik Oldenland described them as aloes. In 1701, Jan Commelin made the first drawing of a gasteria, still known as an aloe. What became Gasteria carinata was originally called Aloe africana flore rubro folio triangulari et verrucoso ab utraque parte albicanti notata. Such phrase names used to describe plants were typical until Carl Linnaeus introduced in 1753 the binomial naming system we use today.

Philip Miller in 1768 named the three known plants that would become gasterias: Aloe carinata, Aloe disticha and Aloe verrucosa. These plants were included in the genus Aloe until 1809, when Henri Duval first suggested the name Gasteria, which was first publicized by Adrian Haworth in 1812 and then in 1827.

Throughout the 1800s and 1900s, there were continual additions and revisions of the species as more and more varieties were found. The most well-known information was provided by Ernst van Jaarsveld in his books: Gasterias of South Africa (1992) and the updated Gasterias of South Africa: A New Revision of a Major Succulent Group (1994). Copies of both of these books are in the HSCSS library.

Van Jaarsveld updated the list of taxa to 34 in 2007, but since then, the list expanded to include 40 taxa as of 2019. The list has expanded and contracted depending on how the species were identified, but in 2014, new molecular studies of aloes indicated that Gasteria should be a separate grouping from aloes and haworthias.

According to Tony Roberts, the genus Gasteria is divided into two sections: Gasteria with nine species and Longiflorae with 20 species. These divisions mainly relate to the shapes of the blooms (bulbous vs. tubular) and leaves (rounded vs. pointed). See the handout in the August HSCSS Digest newsletter, which was provided by Tony Roberts of the British Cactus and Succulent Society, for more information on these sections.

All gasterias start off life in what is known as a distichous or linear form – that is, one leaf appears at a time, with the leaves alternating left and right. Some plants stay that way, while others at adulthood begin to have leaves appear in a more spiral format, resulting in a rosette or rosulate form.

Light Levels

Gasterias prefer bright light or indirect sun, although they can grow in full sun. Be careful, though, as they sun scorch easily. In habitat, many gasterias grow in protected areas, such as under grass or bushes. Gasterias grow well on window sills during the winter, although they like to be outside in the summer.

Watering

Most gasterias can take quite a bit of water during the summer. But during the summer heat, be sure to let them dry out completely before watering again. They grow best in the cool spring and fall, which are also the best times to feed them.

The plants prefer well-draining soil that is very porous and has a high mineral content. If kept inside during the winter, they will need a small amount of water about once a month to keep them from shriveling too much. Do not overwater, as that can result in lanky. thin leaves and possible rot.

Fertilizing

Gasterias do well with a general-type fertilizer given from spring into early fall. Typical cactus/succulent fertilizer works fine for them.

Temperature

Gasterias can easily withstand high summer temperatures, but prefer to have some air movement. They do not want a temperature below 50 degrees F during the winter and prefer to have plenty of ventilation while they rest. They also need bright light during this time. If they are kept cooler during the winter, they are more likely to bloom during the spring and summer.

Propagation

Gasterias are easy to propagate from seed, division of larger plants or leaf cuttings, as they make small plantlets fairly quickly. The plantlets can be treated just like adult plants when watering and feeding.

Remember: If you have seed pods on your gasterias, they are wind-blown. When they open, the seeds may land among your other plants. You need to cover gasterias with a bag, or you will have little gasterias everywhere.

Pests

Most gasterias are generally pest-resistant. As with most succulents, though, you should watch out for mealybugs. They also can suffer from sun scorch (brown spots) on the leaves if they are moved into a sunny area too quickly.

Gasterias are also susceptible to fungal infections (black spots), which are usually the result of too much humidity or water on the leaves. The plants have a natural defense mechanism for this fungus, so they will survive, but you will be left with unsightly spots on the leaves.

Here are some websites and other sources to help with identification and care of your gasterias. You can also read past articles on gasterias in the Plant of the Month section of the HSCSS website.

Websites:

Llifle Encyclopedia of Succulents – Genus: Gasteria – http://www.llifle.com/Encyclopedia/SUCCULENTS/Family/Aloaceae/Gasteria/
Desert Plants of Avalon – How to Care for and Grow Gasteria Succulent Plants – .
http://desertplantsofavalon.com/uncategorized/how-to-care-for-and-grow-gasteria-succulent-plants/
Dave’s Garden – Introduction to Gasterias, Common and Easy Succulents for the Garden and Pottery – https://davesgarden.com/guides/articles/view/2915
Plant Care Today – Gasteria Plant Care: Learn to Grow and Propagate Gasteria Succulents – https://plantcaretoday.com/gasteria-plant-care.html
PlantZAfrica – Plants of the Week (Search for Gasteria) – http://pza.sanbi.org
Succulent Guide.com – Genus: Gasteria – https://succulentguide.com/cactus/?start=0&genus=Gasteria&species=
Succulent Plant Page – The Gasteria Page – https://succulent-plant.com/families/aloaceae/gasteria.html
Wikipedia – https://en.wikipedia.org/wiki/Gasteria
World of Succulents – Gasteria – https://worldofsucculents.com/?genera=gasteria

Print Information:

Succulent Flora of Southern Africa – Court, Doreen – 2010
Beginner’s Guide to Gasteria, Haworthia, Agave and Other Succulent Monocots – Glavitch, Tom – 2015
Cactus and Succulent Journal – Recent Trends in Gasteria Hybridization – Glavitch, Tom; and Schaffer, Scott – September 2014
Essex Succulent Review – Gasterias Galore! – Roberts, Tony – March 2015
British Cactus and Succulent Society CactusWorld – Hunting for Gasteria in the Western and Eastern Capes, Part 1 – Roberts, Tony; and Mercer, Jim – September 2013
British Cactus and Succulent Society CactusWorld – Hunting for Gasteria in the Western and Eastern Capes, Part 2 – Roberts, Tony; and Mercer, Jim – March 2014
Essex Succulent Review – The Cultivation and Propagation of Gasterias – Roberts, Tony – March 2016